Here’s Everything That Happens in Your Grill at Every Temperature
To many, barbecue is a religion. But to its truest practitioners, it’s a broad course of sciences: physics, chemistry, microbiology. The searing and slow-roasting community has a lead researcher in “Meathead“ Goldwyn. His BBQ and grilling-centric site, AmazingRibs.com, is the de facto hub for smokeheads to compare metrics in the interplay of heat, smoke, proteins, fat, and salt.
For people like this, Kingsford has developed their new Long-Burning Charcoal Briquets, for a smoky, slow cook with low ash. But getting different parts of the grill to these temperatures? That’s on you and your judicious use of the charcoal. After all, fire and meat may be science, but hitting those sweet spots is an art. (Which technically makes grilling one of the humanities. Live and learn!)
Meathead takes his temperatures seriously: there’s a narrow bandwidth between pathogenocide and tough meat, and you don’t want to be on the wrong side of either one. He gladly expounded on his catalog of significant temperatures so you understand what’s going on in your grill at sea level (sorry, Denver). We also spoke to Suhail Ansari, a development scientist at Kingsford, to find out what happens on the charcoal side. Now on with the education!
Low and slow, 200º F to 250º F, that’s the way to turn most cheap cuts into best cuts.
Animal fat begins to soften. Way lower temp than you’d think, right? But it would take a long time for fat to reach this temperature if the air itself were 95º F. Heat moves fastest across solids like the grill grate; that’s called conduction. Then, there's indirectly heating, through the hot air within your grill (or in a marinade) via convection. There's also some heat from the infrared light of the charcoals -- their burning gives off heat waves -- that's radiation. Not the kind that will give you Spider-Man powers, sadly; just radiative heat.
Proteins in fish start to denature, but it’s not safe yet because bacteria remain active. Fish filet is more delicate than meat because our finny friends in the water don't have to support their own body weight. Their soft connective tissue, myocommata connects short muscle fibers, and collagen is much less prevalent than in mammals (3% compared to our 15%).
Listeria, the White Walker of food pathogens, reaches its growth limit.
Myofilbrillar proteins really begin to break down. Myofibrils are the long strands of the muscle that contract as thick filaments of protein (mostly myosin) climb along thin ones (mostly actin). They constitute the grain of the meat you’re always told to cut against for less chewing.
Myosin proteins fully unwind, if you’re into that sort of thing. Muscle is 70% water, so you’re going to lose a lot of moisture as the myofibrils shrink. And thus begins the battle against producing a dry piece meat.
At this point your steak is rare, which is an esoteric preference, but an understandable one.
Unless you’re worried about bacillus cereus, the pathogen in every scoop of rice you’ve ever eaten, the FDA says pretty much every other bacterium worth worrying about can no longer reproduce at this temperature. But that doesnot mean you’re killing the ones already there. You’re still in the FDA “danger zone” here, though it’s a question of temperature over time. Grillers regard this range somberly. Sous vide pioneers debate it fervently.
Is there a more magical number in grilling than 130º F? This is where most pathogens begin to die, fat renders into liquid, and beef is a perfect medium rare. To achieve a 6D killrate of bacteria (99.99997%) you’ll have to hold meat at this temperature for almost two hours.
Steak crosses from medium rare into medium. Most bacteria dangerous to humans are dead after 37 minutes at this temperature.
If you can hold poultry at this temperature for 82 minutes you're safe, but since you're grilling and lack the temperature control of a sous vide, aim for an inner temperature of 165º for seven seconds.
Collagen contracts. Myoglobin (the red liquid in every butcher’s package that you mistake for blood) denatures as well. We’ve also hit the upper limit of the FDA “danger zone” for bacterial activity.
Wooo, that chicken you were about to cook for 82 minutes at 136º F is now safe after just 35 at this temperature!
Listeria starts to die, but it takes 17 minutes to get all the little devils.
The USDA calls this the official temperature of medium rare, but AmazingRibs.com says it's medium's the upper border with medium well. You’ll still have some juice in the middle of the cut, but this is the temperature for those who like their outer bite a little drier. You know you can get a crispy sear without drying the meat, though, right?
Internal temperature of 150º F? Your steak is solidly medium well, the outer limits of good taste, in part because the protein actin -- the thin filaments that myosin uses as a stepladder when contracting the muscle -- completely denatures here.
Above the meat’s center, “The Stall” -- that strange moment when meat actually drops in temperature and refuses to rise -- often begins at this point, contingent on air flow and humidity. There were various theories on why this happened, but it was Prof. Greg Blonder -- the scientist in residence at AmazingRibs.com -- who proved it was cooling caused by evaporation.
A lot of BBQers fear the stall, but wise pit masters welcome it; it’s crucial to the formation of bark: that crunchy, chewy, crispy goodness that sheaths the melty, jiggly meat. More on that in a moment.
Collagen begins to denature into delicious gelatin (Meathead says he observes it starting at 160º F). Sploosh! What was once an inedible chewtoy is now one of the most flavorful parts of the beast
Steak goes from medium well to well done. Unless you work for the USDA, who think you're still in medium rare country.
Bacteria die in 30 seconds or less here. But better give it two minutes for poultry.
Beef and sheep are pasteurized instantly. But for the love of that animal’s sacrifice, don’t cook your meat this high. That’s medium well. You’re way better off cooking it at a lower temp for a longer time if you can do so without dehydrating it. Even the Dept. of Health & Human Services says it’s okay to eat whole cuts of red meat once their interior is cooked to 145º F and held there three minutes.
Burger is pasteurized. Ground meat is way more likely to carry pathogens than whole muscle, because the outside surface, where bugs live, becomes mingled with the inside and free to wander.
Your steak is finally medium, says the USDA, who are trying to keep you alive and bless them for that, but that is some tough meat according to everybody trying to eat it.
According to the government, well-done steak is pulled off the grill and served to you philistines, probably with ketchup.
Chicken and other poultry are instantly pasteurized. You can cook to this temp without ruining the meat, but much higher and Meathead warns “you’ll be eating cardboard.” Instead, try out his high/low heat zone method. “You don’t wanna go higher than 165º F, otherwise it’ll dry it out,” he explains. “But let’s say you’re going for 160º F -- if you start it on the indirect side and gently warm it, and bring it up to say, 150º/155º F, you’re still at a risky temperature, and your skin is still soft and rubbery.
“But if you then put it over direct radiant heat -- move it from the indirect side to the direct side -- now you can really crisp that skin, render the fat, and pull it off with really good crispy skin that is not burned.”
Listeria dies instantly, as it should.
Meathead calls this the perfect temperature for grilling potatoes via reverse sear: low heat followed by high heat. “I’ll take a potato, slice it in half, sprinkle it with oil, sprinkle it with a rub, and put it on the indirect side just gently bake it. And then when I’m just about ready to take it off,” he says, his voice taking on a luminous tone, “I’m over the direct heat side and get that skin crispy.”
You’ve slain all the germs! Now here’s where the magic turns your meat mighty.
Water evaporates. No matter how much hotter the grill gets, liquid water won’t get hotter than that: which leads us to an interesting phenomenon…
Meathead recommends a two-zone system of grilling: shove your coals to one corner for direct, concentrated heat around the 325º mark, while keeping another corner empty for an ambient heat of
“Now 225º F is a good temperature,” he says. “At that temperature proteins don’t shrink a lot; when proteins shrink, they squeeze out juices, they get tough.”
If you’re barbecuing -- not just grilling -- 225º F is a magic number for another reason: this seems to be the good balance point for navigating the stall.
Don’t worry that the meat will never finish cooking. Rather, since the stall creates bark, see this period as an opportunity to create a crisp shell.
“Basically, you’re making jerky,” says Meathead. “At a low temp like 225º F, the evaporation cools the meat at the same rate as the convection airflow warms the meat. And so the meat sticks at a temperature until the surface dries out and there’s no more evaporation and makes that “bark” or jerky on the surface.”
Low temperature cooking draws out this process, as the meat’s moisture keeps hitting the evaporation mark, then cooling thanks to that evaporation. It’s especially pronounced in grills with a lack of air flow, or on more humid days (or more humid cuts).
Don’t want bark? Need to get food on the table faster? Turn up the heat, Meathead says. “If you bring it up to say 325º F or 350º F, then the heat from the convection airflow warms even faster than the cooling so the stall is less pronounced, if at all. So the stall is really a phenomenon of cooking at a low temp. You don’t normally hit the stall at higher temps, but it can happen if you do something like spritzing, or mopping.”
Oh yeah, this right here, that’s your sweet spot. The Maillard reaction becomes pronounced at this point -- althought it actually starts below caramelization temperatures -- as sugar and amino acids lock eyes across a crowded room and start reacting to each other to make an unbelievable number of flavor combinations.
Also going on at this temperature: thermal decomposition renders the proteins on the surface of the meat into a thin polymeric film known as the pellicle. You can form one of these at low temps with plenty of air flow, but it’s nice that it speeds up at the same time as the Maillard reaction and the bark formation so they perform some kind of Blue Angels maneuver to make your meat amazing. Let’s face it, 310º F is to the outside of the meat what 130º F is to the inside.
This is the higher indirect heat target for Meathead’s two-zone method:
“I tell my readers, ‘Master three temperatures. Master 225º F, 325º F, and ‘Warp 10.’ Warp 10 is for getting that dark brown surface on the steak, for getting that crispy chicken skin, and that you would wanna do at the end of the cook, not the beginning. We’re always taught to sear first, but that’s wrong when it comes to grilling.”
Careful now: this is where you risk turning a beautiful sear into char, turning that red gold into a grey-brown knob of rubber.
Now it’s time to talk smoke, a mixture of carbon monoxide, carbon dioxide, AND various nitrogen oxides, including nitric oxide. These gases, particularly carbon monoxide and nitric oxide, react with the myoglobin to give meat that beautiful, pink smoke ring that aficionados leer at with mixtures of gluttony and envy.
Like the Maillard reaction, smoke is a complex combination of flavor compounds. Even within a single type of plant matter being burnt, there are more varieties of smoke than there are regional BBQ styles. Meathead explains why for all of them, you want to produce blue smoke:
“It’s burning at higher temperature, it’s burning cleaner, you get fewer impurities in the smoke, you get less char, and it just gives you a better flavor […] If you’ve ever gone to a barbecue competition, and you look at these what they call ‘stick burners,’ or smokers that cook with logs, there’s very little wood in there, and it’s all burning fast and hot with flame. The particle sizes are so small that they’re next to invisible.”
He adds that the billowing white smoke of smoldering wood is second best, but any shade beyond that, you’re adding unsavory impurities to your food.
Softer charcoals ignite around here. Despite being so far down the list, it’s the first thing that’s happened chronologically in this entire heat index.
The composition of the charcoal greatly affects its ignition, according to Kingsford’s Ansari.
“A lot of this is making different formulations,” he says, “Like, ‘Hey, what if we raised char a little, and lower coal and raise lime and lower starch?’ And then test batches of the product and see how it burns.”
Ansari says, “I think it’s surprising how hot you can actually get charcoal. If you use our Professional product -- depending how you use it, you can get it up to 800º F, even maybe 900º Fdegrees. You have to use a ton of charcoal, but you’d get a sear so fast.”
This is probably the range that Meathead calls “Warp Ten.”
Things get crazy when you clock four digits.
“One time we coated the entire inside of a Weber grill with a piece of foil to help the radiative energy come back up for cooking,” says Ansari. “For that one, we blew out the thermometer. It was past 1000º F so we don’t know how hot it was.”
Meathead will make you the best skirt steak you’ve ever had by cooking it atop the starter chimney. “I’ll put a grate on top and cook the skirt steak. Now I’m cooking it at 1,000º F right off that chimney, it’s like the back of an F-16 … and you get a good, dark crust, but you gotta flip it like every minute.”
This insanely high heat subjects the surface of the thin strip of steak straight to the Maillard reaction and breaks down some of the connective tissue without overcooking the interior. Sometimes even a tough cut loves a high and hot cook.